Synopsis:In an abortive attempt to repair the TARDIS and escape his exile, the Doctor makes a landing in the Australian outback. There he is captured and taken to Rudolph Steiner's hi-tech Gemini complex. Steiner intends to launch a missile at Venus which will propel it into Earth's orbit. However, Steiner's assistant, Stephens, has calculated that Steiner's plan will lead to the destruction of Earth. Together with a tribe of Aborigines, the Doctor and Stephens desperately try to prevent Steiner's missile from reaching its target.

Synopsis:Whilst walking on Dartmoor, the Doctor encounters a party of World War II German soldiers. Accidentally transported back in time to Nazi occupied France, the Doctor discovers that a Professor Vedrun is being forced by the Germans to develop a matter transporter. Inadvertenly, the Professor has constructed a device that can move people through time as well as space. With the help of Vedrun and the Doctor, the German commander, Spiegal, intends to journey through time to acquire advanced weaponry which will assure a Nazi victory in the war. When the Doctor and Vedrun are rescued from the chateau by the resistance, Spiegal threatens to destroy a school full of children if the escapees are not returned. With Spiegal's deadline approaching, the Doctor must devise a way to save the children and prevent Spiegal from diverting the course of history.

Synopsis:Having successfully repaired the TARDIS, the Doctor journeys into space and lands on a starship manned only by robots and carrying a cargo of unconscious people. Awakening a girl called Trandi, the Doctor discovers that her people, the Crallicans, have been enticed away from their dying world by the evil Vogans. Taking Trandi in the TARDIS to the starship's destination, the Doctor discovers that the Vogans intend to use the Crallicans as slave labour to mine the Voganite minerals which they depend on. In a pretence of cooperation, the Doctor agrees to shuttle the slave from the ship to the planet's surface in the TARDIS. However, as soon as the operation is complete, the Vogans intend to destroy the Doctor and the TARDIS with a bomb.